AT&T today announced that it has agreed, through one of its subsidiaries, to acquire privately-held Wayport, Inc., for approximately $275 million in cash.

The acquisition means that some AT&T subscribers can now get Wi-Fi access at nearly 20,000 domestic hotspots at no additional charge. “Select” AT&T smartphone customers, AT&T LaptopConnect customers, and AT&T High Speed Internet (including U-verse) subscribers will all benefit from the “free” service.

Wayport’s network includes hotspots in the hospitality, health care, education, and retail sectors, including locations as disparate as the Four Seasons hotels and McDonald’s restaurants.

According to In-Stat, nearly 300 million Wi-Fi-enabled devices were shipped in 2007, with nearly one billion predicted by 2012. AT&T wants those users on its network.

See here for the full story at Wi-Fi Planet.